Whip stock



'Feb, 15, 1938. o. B. TROTTER 2,108,419

WHIP STOCK Filed May 19, 1937 wm h .1, m. I z 1 l J R M 3 m v a m Patented Feb. 15, 1938 UNITED STATES PATENT OFFICE,

ap ueatzii flm t rg fiif x 143.4611

8 Claims. (ci. 255-1) This invention relates to a device for controlling the direction of bore holes and more particularly to a whipstock for use in straightening or changing the direction in which an oil well is being shaped end at its forward face so that when the I whipstock reaches the bottom of the hole the sharpened end will penetrate the formation causing the lower section to swing slightly forward about the-knuckle joint. Thus, the angle'of the deviation of the line'wh'ich the bit is to follow will be increased over what it would be if the whipstock were in one piece. A longitudinal passage is provided through both sections, and

the upper end of this passage is connected to the interior of the drill stem so that while the whipv stock is being lowered the drilling fluid may pass downwardly through and out at the bottom of the whipstock so as to remove any detritus which inay have collected in the hole below the whipstock. A valve in the drill bit or collar closes the opening to the passage in the'whipstock as soon' as the whipstock is in place and the bit begins to move down the whipstock face. All of the drilling fluid is then forced out through'thebit as is customary in rotary drilling practice. 1

- For a better understanding of the invention reference may be had to the accompanying draw- .inginwhieh-- Figure '1 is a vertical elevation of the whipstock ready to be lowered in the hole:

, Figure 2 is a vertical sectional elevation through.

' the upper end of the whipstock showing the bit and the valve for controlling the flowof the drilling fluid;

Figure 34s a section taken on the line 3-3 of Figure 2 looking in the direction of the arrows; I

Figure 4 is a .vertical knuckle joint.'while Figure 5 is a partial vertical section of aslightly modified form of the attaching means and the valve. i

section through the i Referring tothedrawinma whipstockis illus- ,trated as comprising anupper section In and a lower section i2, each of these sections being, ta.- pered with the thinner end uppermost and with the face I! slightly concave as shown in Figure, 3,

to accommodate the drill bit. The upper section it is provided with .a ring l4 adapted to engage a drill collar i6 asby means of a left haniithreaded connection it. The drill collar is of course secured to the lower end of the drill stem or string in any suitable manner. The two sections of the whipstock are hinged together as by means of the knuckle joint 20 shown in Figures 1. and 4. This joint comprises Ia round projection on the uppervend of thelower section and'a similarly shaped groove or socket in the lower end of the upper section. A Whenjthe backs of'the two sections are aligned, as shown in heavy lines in Figure 1, a slight space 22 will exist in front of the joint 20 toallow for ajlimited movement of the 15 lower section with respect to the upper section.

The lower end of the lower section is provided with a sharpened or wedge-shaped projection 24 at the front or face side of the whipstock. When the whipstock is hanging freely from the 0 drill collar the lower section I! will be in substantial alignment with the upper section lil es. shown in full lines in Figural. However; when the lower end of the whipstock reaches the bottom of the hole the projection-24- will engage the g5 formation, and because of the shape of this projectionthe further lowering of the whipstock will cause the lower section to moveforward to the position shown in dotted lines. Kit is assumed that the angle-by which the whipstock is tapered an .is of the order of 2 /2 this angle can be doubled to 5 when the lower section has moved to its forward positionand the whipstock will thus be doubly eflective in straightening or changing the direction of the hole. 35 The whipstock sections l0 and I! are preferably formed of a non-magneticmetal sothat the device can be oriented in the hole through the use of one of the usual well surveying instruments, the movable magnetic needle or member of which 40 would otherwise be deflected by magnetic metal in the whipstock. v F

'When lowering a whipstock near to. the bottom I of abore hole, it is desirable to clean that portion of the hole below the whipstock so that the 45 whipstock in uninterrupted flow even though the two sections may be slightly out of-line, as shown 55 in the dotted lines of Figure 1. The drill collar i6 is also provided with a passage 30 connecting with the usual opening in the drill pipe, not shown. The drill bit 32 which is attached to the drill collar [6 by means of the right hand threaded connection 34 is also provided 'with a longitudinal passage 36 opening at the bottom of the bit so that part or all of the drilling fluid passing downwardly through the drill stem and the passage 30 will pass outwardly ahead of the bit to remove detritus in the .hole in the usual manner.

The drill collar I6 is provided with an opening 38 connecting the passage 30 with the upper end of the passage 26 in the whipstock and this opening 38 has an enlarged space 40 for accommodating a ball valve 42. A plug M threaded into the drill collar serves as a valve seat for the ball 42 but in the position shown in the drawing the ball is held away from the seat it-by means of a pin 46 secured to the whipstock directly across the upper end of the passage 26. In operation, when it is desired to change the direction of a hole, the bit 32 is attached to the drill collar M by means of the right hand threaded connection 34 and the drill collar is then screwed into the ring member ill after which the drill collar is attached to the lower end of the drill stem in the usual manner. In this position, as illustrated more --clearly' in Figure 2, the ball 42 will be held away from its seat 44 by means of the pin 46 and as the whipstock is lowered nearly to the-bottom of the hole part of the drilling fluid which is then pumped downwardly through the passage 30 will pass through the opening 38 and downwardly through the passages 26 and 28 and out at the bottom of the whipstock where it serves to wash away any detritus which may have collected in the hole. The whipstock is then set on the bottom of the hole by the weight of the drill pipe and the projection 24 will penetrate the formation so as to move the lower section 12 forwardly about the knuckle joint 20 to increase the effective deviation of the device.

The drill pipe is then turned in a clockwise direction which causes the unthreading of the left hand connection l8 and the bit 32 is then rotated down the face l3 of the whipstock. As soon as the drill collar I 6 is disengaged from the whipstock ring I the valve 42 will seat, closing the passage 38 and causing all of the drilling fluid to pass through the drill bit. When it is desired to remove the whipstock, the drill stem is pulled In Figure 5 is shown a slightly modified form in which a drill bit 48 is shown connected'directly to the drill stem 50 by the usual right hand I threaded connection 52. The bit is provided with an enlarged shank 54 adapted to be connected .to the whipstock collar 56 by means of a left hand threaded connection 58. The shank of the bit is provided with passages 60 and 62 corresponding to passages 30 and 38 in the form disclosed in Figure 2 and a ball valve 64 cooperates with its seat 66 and an unseating pin 68 in the same manner described with reference to the form shown in Figures 1 through 4. In the form shown in Figure 5 the operation is similar to that already disclosed, a clockwise rotation of the drill stem causing the disengagement of the left hand threaded connection 58 so'that the drill bit can travel down along the face of the whipstock.

of this invention may be made without departing from the spirit and scope thereof, and therefore only such limitations should be imposed as are indicated by the appended claims.

I claim:

1. A whipstock comprising an upper tapered section and a lowered tapered section, a hinged joint between said sections, said lower section being provided at its bottom forward end with a wedge-shaped projection, the arrangement being such that the projectionwill tend to penetrate the formation at the bottom of a hole so as to move the lower section forward about said hinged joint to increase the angle of deviation.

2. A whipstock comprising an upper section and a lower section, each section having an inclined face and being formed of non-magnetic metal, a knuckle joint between said sections and arranged so that the lower section may be moved laterally in the direction of said face, said lower section being provided with a chisel-like projection extending downwardly from the bottom of said lower section and in substantial alignment with said inclined face, said projection adapted to penetrate the formation being drilled to cause the lower section to move about said knuckle joint so as to increase the angle of deviation of said face.

3. A whipstock for controlling the deviation of a well being drilled comprising a longitudinally tapered portion, a ring formed at the upper end of said tapered'portion, a longitudinal passage extending downwardly through said tapered portion with an outlet opening at the bottom thereof, a drill stem extending downwardly through said ring, a bit secured to said drill stem, means on said drill stem for cooperating with said ring to support said tapered portion while the whipstock is being lowered into the well, said drill stem and bit being provided with a passage for conducting drilling fluid into the well below the bit, and said drill stem being provided with a conduit connecting the passage in the drill stem with the passage in said tapered portion, the arrangement being such that part of the drilling fluid will pass from the stem in to and downwardly through said tapered portion so as to remove detritus from the well below the whipstock.

4. A whipstock for controlling the deviation of a well being drilled comprising a longitudinally tapered portion, a ring formed at the upper end of said taperedportion, a longitudinal passage extending downwardly through said tapered portion with an outlet opening at the bottom thereof, a drill stem extending downwardly through said ring, a bit secured to said drill stem, means on said drill stem for cooperating with said ring to support said tapered portion while the whipstock is being lowered into the well, said drill stem and bit being provided with a passage for conducting drilling fluid into the well below the bit and said drill stem being provided with a conduit connecting the passage in the drill stem with the passage in said tapered portion, a valve in said conduit normally closed by the pressure of the drilling fluid while the bit is being rotated to drill the hole, and means for holding said valve open while the whipstock is being lowered so that partof the drilling fluid will pass downwardly through and out at the bottom of the whipstock.

5. A whipstock for controlling the deviation of a hole being drilled, a longitudinal passage extending downwardly through and having an outlet at the lower end of said whipstock, a drill stem, a drill collar on said stem, a bit secured increase the angle of aligned longitudinal.

to said drill collar, means for supporting said whipstock trom said collar while being lowered into the well, said drill stem, collar and bit being provided with a passage for conducting drilling fluid downwardly and out into the hole ,below said bit, a conduit in said drill collar connecting the passage in said collar with the passage in said whipstock, a valve in said conduit adapted to be closed during drilling operations of the bit, and means tor holding said valve open while the whipstock is being lowered in the hole.

6. A whlpstock comprising an upper section and a lower section, said sections being formed of non-magnetic metal, a hinged joint between said sections, said lower section be provided at its bottom forward end with a w e-shaped projection, the arrangement being such that as the whipstock is lowered the projection will tend to penetrate the formation and to move the lower section forward about deviation, said upper and lower sections being provided with substantially passages for conducting drilling fluid downwardly through said whipstock as the latter is being lowered into a well, said passages being connected in end to and relation through said hinged joint.

7. A whipstock for controlling the direction 0! a drill bit secured to a drill stem, comprising a longitudinally tapered portion, a ring at the upper end or said tapered portion, a threaded connection between said ring and said bit, a passage said hinged joint so as to 'pin disposed across the extending downwardly through aid drill stem and bit, a second passage extending downwardly through and having an outlet at the bottom of saidvtapered portion, a conduit in said bit connecting said first mentioned passage with said second passage, a check valve adapted to close said conduit when said bit and collar are disjoined and means for rendering said valve inoperative when said bit and said ring are in threaded. connection.

8. A whipstoclrior controlling the direction 'of' a drill bit secured to a drill collar by a right hand threaded connection, comprising a longitudinally tapered portion, a ring at the upper end of said tapered portion, a left hand threaded connection between said ring and said collar, a pass'age extending downwardly through said drill collar and bit, a second passage extending downwardly through and having an outlet at the bottom of said taperedjportion, a conduit in said collar connecting said first mentioned passage with said second passage, a check valve adapted to close said conduit when said collar and rin are disjoined and means for rendering said valve inoperative when said collar and said ring are in threaded connection, said means including a opening of said second passage adjacent said conduit and adapted to hold said check valve open when said collar and ring are in threaded connection.

91min. mom. 

